Author Topic: RM250C / PE250C Engine Cases  (Read 2908 times)

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Offline BAHNZY

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RM250C / PE250C Engine Cases
« on: April 21, 2010, 01:28:56 pm »
Is there any reason that would stop me using a 78-PE250C left side engine case in place of a damaged 78-RM250C case?
I have checked the part numbers for the case and they have different Suzuki numbers, which I would expect.
Have also visually checked the cases and they look to be identical, aside from some extra webbing around the sprocket cover retaining bosses.

Rod
Rod (BAHNZY) Bahn

Offline SUZUKI311

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Re: RM250C / PE250C Engine Cases
« Reply #1 on: April 21, 2010, 07:22:05 pm »
Rod, not 100% sure, but i seem to recall something about stator mount/wire exit  being different? i did have a set of PE cases to compare with my RM, but shifting house has meant they are buried somewhere in a 60x30 shed...
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Offline BAHNZY

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Re: RM250C / PE250C Engine Cases
« Reply #2 on: April 21, 2010, 08:16:55 pm »
SUZUKI311,
Yes there is a difference. The RM has the stator wiring exit through a notch in the stator cover whereas the PE wiring exits via a notch in the actual left side crank case. The RM case that i have (that is damaged) has a OEM Suzuki rubber 1/2 moon seal filling the notch in the crankcase. From what i can work out, the crankcases look the same whereas the stator covers differ due to the notch for the stator wiring on the RM.

Still i want to be sure if they interchange.
Rod (BAHNZY) Bahn

Offline lukeb1961

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Re: RM250C / PE250C Engine Cases
« Reply #3 on: April 21, 2010, 10:21:32 pm »
The cases were slightly different internally to allow a few extra mm for.. something.. I feel it might have been a larger gear that needed clearance. That was the only "real" difference I can recall. One would take both gearsets, the other was a very tight fit.
Luke

Offline LWC82PE

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Re: RM250C / PE250C Engine Cases
« Reply #4 on: April 21, 2010, 10:31:32 pm »
Yes you might want to compare crank case volume.(crank compartment, not gear box compartment) From memory there is a difference between RM250 T and PE250 T/X/Z so there could be that difference on the 78 RM/PE too.
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Offline TT5 Matt

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Re: RM250C / PE250C Engine Cases
« Reply #5 on: April 22, 2010, 05:01:52 am »
why not start compering common parts like cranks,gearshafts,shifter drums and gear set widths,base and centre case gaskets chances are if there the same it will work and easy using alpha sports site which shows up parts numbers in red if you have clicked on them before on another model

oldfart

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Re: RM250C / PE250C Engine Cases
« Reply #6 on: April 22, 2010, 04:18:43 pm »
Difference in Rm 250 T  V  Pe 250 TX    cases .....   is gearbox has an extra gear  ;)

Offline LWC82PE

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Re: RM250C / PE250C Engine Cases
« Reply #7 on: April 22, 2010, 05:12:41 pm »
Did you tell me that the volume was different because one had bigger or smaller crank webs?
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Offline BAHNZY

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Re: RM250C / PE250C Engine Cases
« Reply #8 on: April 22, 2010, 05:49:39 pm »
why not start compering common parts like cranks,gearshafts,shifter drums and gear set widths,base and centre case gaskets chances are if there the same it will work and easy using alpha sports site which shows up parts numbers in red if you have clicked on them before on another model
Matt,
The engine that was in the bike was a PE250C engine with a RM250C gear set so i know that the RM gear set will fit the PE cases. Some time back I got a RM250C engine from GMC that had a loose stator plate. In the time that the plate had been loose it has destroyed the plate centring lugs, hence why i need to replace the left side case. I have checked items like output shafts, gaskets, seals etc and they are common between the PE&RM for the C model. The right side crank half and the con rod are the same between both with the difference being the left crank half that is longer to accommodate an external flywheel for the PE vs. a shorter unit for the inner rotor on the RM.
Rod (BAHNZY) Bahn

Offline lukeb1961

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Re: RM250C / PE250C Engine Cases
« Reply #9 on: April 23, 2010, 07:02:23 pm »
Difference in Rm 250 T  V  Pe 250 TX    cases .....   is gearbox has an extra gear  ;)
That was it!  see what happens when you aren't paying attention?

Offline BAHNZY

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Re: RM250C / PE250C Engine Cases
« Reply #10 on: May 30, 2010, 10:08:22 am »
Right hand RM case and a left hand PE case seems to be o/k.
Aside form a clutch issue, the engine is together and running and seems to be o/k. Run in and first ride will be at Classic Dirt so we'll see how she goes.
Rod (BAHNZY) Bahn